Contact Dermatitis-Irritant

Epidemiology

  • Prevalence: accounts for about 80% of cases of contact dermatitis
  • Association with Atopy: increased

Etiology

Acids

Alkalis

  • Ammonia (see Ammonia, [[Ammonia]])
  • Bleach (see Chlorine, [[Chlorine]])
  • Detergent
  • Drain Cleaners
  • Lye
  • Oven Cleaners
  • Soaps
  • Toilet Bowel Cleaners

Bromine/Chlorine(see Chlorine, [[Chlorine]])

  • xxx

Hydrocarbons (see Hydrocarbons, [[Hydrocarbons]])

  • Cutting Oils
  • Lubricating Oils
  • Petroleum

Other Chemicals

  • Creosote: acts as a contact irritant, sensitizer, and photosensitizer
  • Asphalt/Tar Products

Spurge Plants

  • General Comments: produce irritating white milky sap
  • Candelabra Cactus
  • Euphorbia Milii (Crown of Thorns, Christ Plant, Christ Thorn) (see Euphorbia Milii, [[Euphorbia Milii]])
  • Euphorbia Pulcherrima (Poinsettia) (see Euphorbia Pulcherrima, [[Euphorbia Pulcherrima]])
  • Euphorbia Tirucalli (Firestick, Pencil Cactus, Pencil Tree, Aveloz, Indian Tree Spurge, Naked Lady, Sticks on Fire, Milk Bush) (see Euphorbia Tirucalli, [[Euphorbia Tirucalli]])
  • Poinsettia (see Poinsettia, [[Poinsettia]])

Calcium Oxalate-Containing Plants

  • Dieffenbachia
  • Daffodil
  • Hyacinth
  • Pineapple

Physiology

  • Mechanism: direct injury to keratinocytes of the skin -> non-immune mechanism
    • Sensitization is not required
    • Involves the innate immune system
    • Concentration of Agent: more critical to pathogenesis of irritant contact dermatitis than in allergic contact dermatitis

Diagnosis

  • Patch Testing: negative
  • Skin Biopsy: typically nonspecific

Clinical Manifestations

  • Latency of Reaction After Contact: usually within 48 hrs
  • Geographic Pattern
    • Typically sharply demarcated and limited to the contact site
  • Variable Presentation: may present as any of the following
  • Other Clinical Features
    • Although may be pruritic, irritant dermatitis is typically has burning or “prickling” pain
    • Cumulative irritant dermatitis most commonly affects thin exposed skin regions (back of hands, between fingers, face, eyelids): long-term exposure may result in pruritus, folliculitis, calcifications, or acneiform rash
    • Melanoderma: may occur with creosote or asphalt/tar products

Treatment

  • Latency to Resolution: typically diminishes spontaneously within 96 hrs

References

  • Contact urticaria due to the common stinging nettle (Urtica dioica)–histological, ultrastructural and pharmacological studies. Clin Exp Dermatol. 1991 Jan;16(1):1-7
  • Compositae dermatitis. Australas J Dermatol. 1999 Aug;40(3):123-8 [MEDLINE]
  • Long-term safety and toxicity of azathioprine in patients with air-borne contact dermatitis. Indian J Dermatol Venereol Leprol. 2001 Mar-Apr;67(2):75-7 [MEDLINE]
  • Contact allergy to herbal teas derived from Asteraceae plants. Contact Dermatitis. 2006 Apr;54(4):196-201 [MEDLINE]
  • Compositae dermatitis from airborne parthenolide. Br J Dermatol. 2007 Mar;156(3):510-5
  • A systematic approach to systemic contact dermatitis and symmetric drug-related intertriginous and flexural exanthema (SDRIFE): a closer look at these conditions and an approach to intertriginous eruptions. Am J Clin Dermatol. 2011 Jun 1;12(3):171-80 [MEDLINE]